AuthorTopic: DCS-935L Not available after power outage (Read 6223 times)

We have had a few instances where the power has cut out recently (once for a few seconds, once for about a minute). I have a DNR-202L, DCS-5222LB1, and 2 DCS-935L's in my network. Everything came back on line except for the 935l's. The 935l's were not available through the DNR-202L website or iPhone app or the mydlink Lite application. The 5222LB1 was available and was showing the video from the camera.

The 935l's had a green light on the back, but just were offline everywhere. (I didn't think about this at the time, but I should have also seen if local web access was available. Something to do with the next thunder storm).

Everything has the most recent firmware.

I powered down the cameras. When I plugged them back in, everything is working fine.

Has anyone else seen this issue? Right now it's not a big problem, because I'm at the house where they are installed. But, in 2 weeks, I'll be spending an extended period of time at our second house. Then, it's a real issue if it happens and I'm not home.

I would test one 935L alone with a static IP address. Turn off ALL other devices on 2.4ghz and then pull the power adapter for the 935L to simulate a power failure. Plug in and test.

What wireless modes are configured on the router? Mixed modes? What wireless security settings are configured on the router? Mixed or WPA2 only? Recommend WPA2 and AES only. Can try WPA2 and TPIK only and test to see if same thing happens with camera.

I've been able to recreate the problem (step 1 in any debugging situation). I wanted to make sure I could recreate the problem before I started to randomly messing around with settings.

So, simply pulling the power isn't enough to cause the issue. I have to have the router powered down when I restart the camera. Then I get the issue where the camera isn't available anywhere. (BTW, the local web access doesn't work--that makes sense now.)

When I recreated the problem, I did notices that there was an extra wireless network in the list of available wireless networks. It matches the WiFi Name(SSID) listed on the back of the camera.

It appears that if the wireless network configured in the camera isn't available, the camera defaults to create on itself (probably so that it can be configured).

It looks like the router is taking longer than the camera to boot up and start accepting connections. So, the camera is creating the configuration WiFi network because it can't connect to the one it's configured for.

I've just configured the 935L for a static IP and it is still creating the camera based WiFi if the configured network isn't available.

I've looked and I don't see a configuration setting in the camera to control this. Is there a way to turn that off and have it continue to look for the configured network?

(BTW, the router is configed for mixed wireless modes [on both 5GHz and 2.4Ghz], and is configured for WPA2/AES).

Ok, sounds like the router is taking longer than the cameras are currently programmed to wait for and thus will create there own. Just curious, how long does it take for the router to reboot and come to ready and accept connections?

It looks like the SSID for the router shows up on the iPad about 60 seconds after the router is rebooted.

However, I was watching the LED on the back of the camera. It was a full 126 seconds before it turned green. Of course, without knowing how D-Link implemented their looking for network routine, it's impossible to know if all of that time was waiting for the router to reboot.

Of course, this did show a little bit more of how the camera is coded. If I only rebooted the router, the camera connected to the router when it became available. So, the logic to turn on the configuration WiFi network is only invoked during a power cycle.

I presume this maybe something that D-Link needs to review. I'll pass this on to D-Link and see if there is any information on it. You might want to phone contact them directly and let them know about this as well.

I ran out of time to work on this yesterday. So, I contact D-Link support via email and included a link to this thread.

I think the first thing I'm going to do is get a UPS for the router and cable modem. That should eliminate the problem during brief power outages. We added one to our second house out in Utah, and it has been really nice. Especially since where we are in Utah is apparently the longest run of lines from a power station--we have a lot of small power outages out there.

Oh, and thanks for the help yesterday--it was fun! I used to be a programmer/architect and dealt with networks all the time. It was nice to see that I can still troubleshoot and debug!

Ya I have a UPS on my ISP and router system so I have a 30 minute time frame after power goes out. We usually don't see any outages more then that up here.

Ya, talking to D-link, they think there is a router/camera timing issue that seems to be exceeding the cameras default time out before it switches to AP mode. Any chance you can test a different router to see what happens?

Glad to be of some help. Just pointing areas to look at first and debug. Ya, I'm a debugger.

I have to apologise but I don't know what I was thinking - my cameras which display the exact same symptoms are 936L's, not the 935.

My routers are Apple routers, and after every power failure, the 936 cameras show their own wifi network. And once they have failed to connect, no matter what I try, they do not reconnect and I have to do the setup again. (I.e. even rebooting the cameras with the router on makes no difference and they have to be re-configured again. I have 5 of them and at first only one displayed this behaviour, but 3 are now having this issue (2 at home and 1 at the holiday home)) For what it's worth, they are all hardware version A1 with Firmware 1.02.